Circular knitting machines for the production of hosiery with double, outwardly turned-over welts



' June 7, 1966 R. TENCONI 3,254,509 CIRCULAR KNITTING MACHINES FOR THE PRODUCTION OF HOSIERY WITH DOUBLE, OUTWARDLY TURNED-OVER WELTS Filed May 12, 1965 9 Sheets-Sheet l R. TENCONI CIRCULAR KNITTING MACHINES FOR THE PRODUCTION OF HOSIERY WITH DOUBLE, OUTWARDLY TURNED-OVER WELI'S Filed May 12, 1965 9 Sheets-Sheet 2 June 7, 1966 R. TENCONI 3,254,509

CIRCULAR KNITTING MACHINES FOR THE PRODUCTION OF HosIERY WITH DOUBLE, OUTWARDLY TURNED-OVER WELTS Filed May 12, 1965 9 Sheets-Sheet 3 June 7, 1966 y CIR ULAR R. TENCONI 3,254,509 G MACHINES FOR THE PRODUG ION OF HOSIER WE 5 Filed May 12, 1965 9 Sheets-Sheet 4 June 7, 1966 R. TENCONI 3,254,509 CIRCULAR KNITTING MACHINES FOR THE PRODUCTION OF HOSIERY WITH DOUBLE, OUTWARDLY TURNED-OVER WELTS Filed May 12, 1965 9 Sheets-Sheet 5 June 7, 1966 R. TENCONI 3,254,509

CIRCULAR KNITTING MACHINES FOR THE PRODUCTION OF HOSIERY WITH DOUBLE, OUTWARDLY TURNED-OVER WELTS Filed May 12, 1965 9 Sheets-Sheet 6 J B 0* k A June 7, 1966 R. TENCONI 3,254,509

CIRCULAR KNITTING MACHINES FOR THE PRODUCTION OF HOSIERY WITH DOUBLE, OUTWARDLY TURNED-OVER WELTS Filed May 12, 1965 9 Sheets-Sheet 7 June 7, 1966 R. TENCONI CIRCULAR KNITTING MACHINES FOR THE PRODUCTION OF HOSIERY WITH DOUBLE, OUTWARDLY TURNED-OVER WELTS 1965 9 Sh Filed May 12 eats-Sheet 8 UUUL jU BUU U U WLTMHP MO (LN (U7 (DO 6, W PW P V H 1 "E JE UUM W UUUUUUU ATTORNEY R. TENCONI June 7, 1966 CIRCULAR KNITTING MACHINES FOR THE PRODUCTION OF H IERY WITH DOUBLE, OUTWARDLY TURNED-OVER WELTS Filed May 12, 1965 9 Sheets-Sheet 9 FIG. 24.

INVENTOR RICCARDO TE ONI A TTORNE Y United States Patent CIRCULAR KNITTING MACHINES FOR THE PRO- DUCTION 0F HOSIERY WITH DOUBLE, OUT- WARDLY TURNED-OVER WELTS Riccardo Tenconi, Varese, Italy, assignor to Marcella Sessa Moretta, Varese, Italy Filed May 12, 1965, Ser. No. 455,263 Claims priority, application Italy, May 21, 1960, Patent 629,940; Nov. 39, 1962, 23,fi94/62 11 Claims. ((31. 66-41) This invention relates to circular knitting machines for the production of hosiery, such as stockings and socks, with double, outwardly turned-over tops or welts, and the present application is a continuation-in-part of my copending applications for US. Letters Patents, identified as Serial No. 110,809, filed May 17, 1961, and Serial No. 325,593, filed November 22, 1963, both abandoned.

Most circular knitting machines presently in use for the production of hoisery with double, turned-over tops or welts include special mechanisms for the purpose of retaining the initial courses of top or welt during the entire knitting of the latter, and then to carry these initial courses back and join them to the leg of the hoisery or stocking so as to form a double, inwardly-turned top or welt. Such special mechanisms provided for temporarily retaining the initial courses of the top or welt include transfer bits which are radially movable in the slits of a dial rotatably supported in the cover of the knitting machine so as to be located coaxially above the needle cylinder, and drive mechanisms connecting the dial with the needle cylinder to ensure that the rotary movements of the dial will be perfectly synchronized with those of the needle cylinder. This type of knitting machine construction gives rise to difliculties and complications that are well known, and further disadvantageously increases the bulk of the mechanisms disposed at the upper part of the knitting machine.

Various arrangements have been proposed for eliminating the transfer bits, the dial in which they are supported and the driving means therefor. In these previously proposed arrangements, the regular knitting needles are used for the production of the double welt and special sinkers are provided which have an additional or lower groove below the usual knitting level or cast-off ledge to form a lower cast-off ledge. In such proposed machines, the loops of the first course, or of a few initial courses, are held so low on the needle shafts by the additional lower grooves of the sinkers during the formation of the double welt that they cannot be cast off, and these retained loops are released,-after the welt is completed, to knit the released loops together with a further course.

In a known machine of the above type, all the sinkers are of the special configuration to provide the additional or lower grooves and, when knitting the first course of the top or welt of a stocking, only alternate sinkers are retracted or moved radially outward to the extent necessary to deposit the yarn or thread in the additional grooves of these retracted sinkers where the yarn is held when the sinkers are advanced or moved radially inward again until the double top or welt has been completely knitted. With the foregoing arrangement, the stitches or loops of the first course are held sufiiciently low on alternate needles so that the same cannot be cast off during the formation of the following courses, at which time all of the needles are operating. When the top or welt has been completely knitted, those sinkers which held down respective stitches or loops of the first course are again retracted or moved radially outwardly to release the stitches which are then joined to the leg of the stocking. The disadvantage of this arrangement is that it requires selective control of the sinkers by means of a device which is not normally provided on a circular knitting machine so that the design of the latter is complicated. Further, trouble may arise during the knitting operation by reason of the fact that the stitches of the first course which are retained in the additional grooves of alternate sinkers occupy inclined positions and therefore may rise on the needle stems and risk the danger of being dropped or cast 01f.

According to another recent proposal, a circular knitting machine is provided with two dilferent types of sinkers, that is, special sinkers having the configuration described above so as to present additional grooves below the normal knitting level, and ordinary sinkers, with two special sinkers being alternated with two normal sinkers throughout the set of sinkers. In such an arrangement, only the needles disposed between pairs of special sink-. ers retain stitches or loops of the first course on their stems. This arrangement has the disadvantage that'two different types of sinkers have to be arranged in the knitting machine and, apart from the additional grooves provided in the special sinkers, the profiles of the special and ordinary or conventional sinkers have to match exactly so as to ensure uniformity of the knitted fabric. Such matching profiles require that the special and ordinary or conventional sinkers be cut by perfectly matching dies and, in the cast of breakage of sinkers necessitating the replacement thereof, perfectly matching sinkers of the two types must be available. Furthermore, in this arrangement, it is apparent that the first course is only held on every fourth needle during the knitting of the top or welt of the stocking, instead of on every second needle or alternate needles, as is usually the case.

This may lead to difficulties during operation on account of the long distances between the stitches that are retained on the needle stems, and also on account of the reduced strength of the joint or connection between the turnedover welt or top of the stocking and the leg thereof.

It is an object of this invention to provide circular knitting machines for the production of hoisery with double, outwardly turned-over tops or welts, in which the turned-over tops or welts are produced by the needles and sinkers which knit the other portions of the hosiery, that is, without resort to transfer bits and the like, and wherein one avoids the above disadvantages of the previous proposals for eliminating the use of such transfer bits.

Knitting machines embodying this invention are generally of the type in which all the sinkers are of a special configuration to provide two knitting levels or cast-off ledges and an additional groove disposed below the upper knitting level, and such sinkers are actuated so as to be retracted or moved radially outward, at least during the knitting of the first two courses of the top or welt, to the eX- tent required to form the stitches of such first two courses on the lower level or ledge of the sinkers, whereupon the sinkers are moved radially inward or advanced to form the stitches of the remaining courses of the top or welt on the upper knitting levels thereof. The two or more initial courses of the welt knitted on the lower knit-ting levels of the sinkers are joined to the following courses knitted on the upper levels by means of a binding or joining course, but are held down by the additional grooves of the sinkers until the completion of the knit-ting of the top or welt, after which the sinkers are retracted or moved radially outward sufiiciently to release, the lower knit, that is, the courses knitted on the lowerknitting levels of the sinkers, and join it to the leg of the hosiery or stocking.

The above mentioned disadvantages of the previous proposals for eliminating the use of transfer bits is avoided, in accordance with this invention, by reason of the fact that all of the sinkers are of the same type and are always controlled in the same way so that a device for selection of the sinkers is not needed. Further, the stitches of the some difliculties relating to the joining or connecting of the knit formed during at least the first two courses on the lower ledges or levels of the sinkers and the knit subsequently formed on the upper knitting levels of the sinkers. At this joining stage of the knitting process, the same yarn or thread is used for knitting both on the lower and upper levels of the sinkers so that there are long stitches in the joining or binding course and this requires a faster thread feed of the thread pulled by the needles with possible excessive strains causing breakage of the thread. Such difficulties have been overcome in machines embodying this invention by lowering only selected needles, for example, alternate needles, during the joining of the courses knitted on the lower and upper levels, respectively, of the sinkers in order to reduce the tensions in the thread or yarn and thereby substantially avoid the danger of thread breakage.

In accordance with an important aspect of this invention, a circular knitting machine for the manufacture of hosiery with double outwardly turned-over tops or welts has a needle cylinder carrying alternately arranged needles with long and short butts, respectively, a main knitting cam for actuating the needles and a main sinker cam for retracting the sinkers during normal knit-ting operation, a supplementary needle cam associated with the main knitting cam and operative to increase the downstroke of the needles, a supplementary sinker cam asso ciated with the main sinker cam for further retracting the sinkers, and actuating mechanisms for the supplementary needle and sinker cams rendering the supplementary cams both operative during knit-ting of at least the first two courses of the double top or welt, thereby to form the stitches of these first courses at the level of the lower knitting ledges of the sinkers, and, during the knitting of the immediately following course which is to serve to bind or connect the courses knitted at the lower and upper levels, respectively, rendering the supplementary sinker cam inoperative while the supplementary needle cam remains operative to increase the down-stroke of at least the long-butt needles. Thereafter, the supple mentary needle cam is rendered completely inoperative with respect to all of the needles so that, during the knittin-g of the remainder of the double top or welt the knit is formed on the upper ledges or levels of the sinkers and is joined to the first course which are held downon the stems of the needles.

In one embodiment of this invention, radially adjustable needle lifting and lowering cams are positioned in advance of the yarn or thread feed or guide. The needle lifting cam is selectively engageable with both the long and short-butt needles, or only with the long-butt needles, for raising the engaged needles to a level where they can take the thread from the yarn guide, and the needle lowering cam is selectively engageable with the long-butt needles below the level where they can take the yarn from the guide, thereby to determine those needles which are operative during each course of the knitting operation.

In another embodiment of this invention, the adjustable needle lifting and lowering cams provided in advance of the yarn feed are replaced by a single adjustable needle lifting cam having its radial movements controlled so that, during the formation of the first course, it raises only the long-butt needles to a level at which their latches are cleared or shed and the needles take the thread from the thread or yarn guide, it raises all the needles during the knitting of at least one additional course following the first course, and at which time the supplementary cams associated with the main knitting cam and the main sinker cam are both operative, and it also raises all the needles during the knitting of the next course, at which time the supplementary sinker cam is no longer operative, and finally the single additional needle raising cam is rendered inoperative with respect to the short-butt needles, either during the knitting of the following course or the one after that, prior to.being returned to its position where it acts to raise all of the needles for the knitting of the remainder of the welt and the other portions of the stocking.

In this last mentioned embodiment of the invention, the usual needle lowering or knitting cam is permanently operative with respect to all of the needles during the knitting of the entire welt and of the other sections of the stocking or hosiery. This embodiment of the invention has the advantage of reducing the number of movable cams, thereby to simplify the mechanisms required and the possibility of defects in operation, and further of improving the uniformity and appearance of the knit, particularly at the joining or binding together of the courses knitted on the lower and upper levels, respectively, of the sinkers.

The above, and other objects, features and advantages of the invention, will be apparent in the following detailed description of illustrative embodiments thereof which is to be read in connection with the accompanying drawings, wherein:

FIG. 1 is a schematic, vertical sectional view of a circular knitting machine of a.type that may embody this invention;

FIG. 2 is a developed view of the needle cam assembly of a knitting machine in accordance with one embodiment of this invention;

FIG. 3 is a developed view of the sinker cam assembly;

FIG. 4 is a bottom view of the sinker cam assembly;

FIG. 5 is a detail sectional view taken along the line V V of FIG. 4;

FIG. 6 is a perspective view of a device for actuating the sinker controlling cams;

FIG. 7 is a perspective view of a device for actuating the needle controlling cams;

FIG. 8 is a side elevational view of a sinker that may be used in the circular knitting machine embodying this invention;

FIG. 9 is a view similar to that of FIG. 8, but showing a preferred form of sinker for use in circular knitting machines embodying this invention;

FIGS. l0, l1 and 12 are diagrammatic views showing several sinkers and needles of the knitting machine in three successive stages during the knitting of a double, outwardly turned-over welt in accordance with this invention;

FIG. 13 is a diagrammatic view similar to that of FIGS. l0, 11 or 12, but illustrating a variation in the melthod of knitting the double, outwardly turned-ove we t;

FIG. 14 is a diagrammatic sectional view showing the upper part of a stocking or hosiery having a double, outwardly turned-over welt in accordance with this inventron;

FIG. 15 is a diagrammatic developed view showing the arrangement of the needles in the needle cylinder and of the sinkers in the sinker supporting ring of a knitting machine embodying this invention;

FIGS. 16 and 17 are developed views similar to those of FIGS. 2 and 3, respectively, but showing the needle and sinker cam assemblies of a machine in accordance FIG. 22 diagrammatically illustrates the interlacing of the first six courses of a stocking knitted in accordance with the operations illustrated in FIGS. 18 to 21;

FIG. 23 diagrammatically illustrates a modification of the interlacing shown on FIG. 22; and

- FIG. 24 is an enlarged diagrammatic view of the interlacing of the first three courses shown on FIGS. 22 and 23.

The drawings show only those parts of a conventional circular knitting machine for the manufacture of hosiery which are absolutely necessary for understanding the invention. Naturally all other parts of the knitting .machine, which are neither illustrated nor described, are conventional and can be constructed so as to operate in a manner consistent with the corresponding parts of existing circular knitting machines. In order to simplify the specification and drawings, the invention is disclosed herein as being embodied in a single-feed machine, but it is to be understood that the invention may be similarly applied to machines having a plurality of feeds.

Referring to FIG. 1 in detail, it will be seen that the circular knitting machine there shown essentially comprises a cylinder 1 having a sinker supporting ring 2 secured on its upper end portion. Latch type needles 3 are vertically movable in axial grooves formed in the outer surface of cylinder 1, and the needles are held in the related grooves by the turns of a surrounding helical spring 4.

Sinkers 5 are displaceable in radial grooves of the sinker supporting ring 2 and are surrounded by a spring ring 6 which urges the sinkers radially inward. The cylinder 1 is secured on a tubular sleeve 7 which is rotatable in the machine frame 3 and provided with an outer ring gear 9 which meshes with a spur gear 10. Gear 10 is secured on a shaft 11 journaled in the frame 8, and which is driven by a motor (not shown). Arranged coaxially around the lower part of sleeve 7 is a main control drum 12 which is suitably turned and controls the entire cycle of the knitting machine in the usual manner.

A ring 13 is secured on the machine frame above the sinker supporting ring 2 and carries the cam for controlling the sinkers 5. FIG. 1 shows also a thread guide arm 14 which feeds the thread to a point in the vicinity of the upper edge of the needle cylinder where it can be engaged by the needles 3. Fixedly supported about the needle cylinder 1 is the cam assembly 15 for controlling the needles 3.

The machine parts described above correspond to those generally provided in all known circular knitting machines for the production of stockings and socksand the operation thereof is similarly well known.

Specially designed sinkers are used in the machine according to the invention, and such sinkers may have, for example, the configuration shown on FIG. 8 or an FIG. 9. The two types of special sinkers shown on FIGS. 8 and 9 and there generally identified by the reference nurnerals 5 and 5, respectively, are generally alike in that they are each provided with two cast-off ledges or knitting levels, that is, a lower ledge or level 16 or 16 and an upper ledge or level 17 or 17' which is disposed radially outward with respect to the lower ledge. Between these two cast-off ledges or knitting levels, the sinkers are I formed with an additional nose or spur 18 or 18' disposed below the usual nose or spur 19 or 19. The two noses define a lower groove or notch 20 or 2% under the nose 18 or 18 and an upper groove 21 or 21 between the noses 18 and 19 or 18' and 19'. Each sinker further has a stop 22 or 22' for the spring ring 6 to act against, an upwardly directed butt 23 or 23, and a guide slot 24 or 24' which opens radially inward.

As represented schematically on FIG. 15, where the upwardly extending sinker butts are shown developed in a horizontal plane, a portion of the sinkers inserted in the radial grooves of the sinker supporting ring 2 have a short butt 23a and the remaining portion of the sinkers,

6 which are all grouped together, have a long butt 23b. The reasons for these different lengths of the sinker butts will be explained more fully below.

FIG. 2 shows some of the important cams of the assembly 15 for controlling the needles 3; The illustrated cams include the central upper cam 26, the left-hand knitting 'or withdrawing cam 27, and the right-hand knitting cam 28 which is shown in broken lines and which is made operative only during the knitting of the heels and toes of the hosiery, that is, during oscillating movement of the needle cylinder. An additional or supplementary cam 29 is located adjacent the lower end of the left-hand knitting cam 27 and is effective to increase the downward stroke of selected needles to a predetermined extent when such cam is disposed in certain operative positions, as hereinafter described in detail. The cam assembly 15 further includes a lifting cam 30 which is operative to lift the needles to a level at which the latter clear or shed their latches, and an additional cam 31 which is operative to lower selected needles so that the lowered needles cannot engage the thread fed by the guide arm 14. Finally, a profiled guide ring 32 is provided to slidably support the butts of the needles 3 and to raise the needles to a level at which the needles can engage the thread or yarn fed by guide arm 14. The arrow 33 on each of FIGS. 2, 3 and 15 indicates the normal direction of movement of the needles relative to the cams during the continuous rotation of the needle cylinder 1.

Each needle 3 has a butt 34, and these butts are of four different lengths. The needles are arranged in the grooves formed in the outer surface of cylinder 1 so that relatively long and short needle butts are alternated whereby a certain selection of the needles is possible, as will be explained below. In order to permit the engagement and disengagement of the earns 27, 29, 30 and 31 by radial movement thereof toward and away from the circumference of the needle cylinder, the needles in a limited on FIG. 15, with long butts 340 which .are shorter than the long butts 34a of the needles in the rest of the needle set, and with short butts 34d which are shorter than the short butts 34b of the needles in the rest of the needle set. However, it should be noted that, over the entire circumference of the needle cylinder, a needle with a,

relatively longer butt 34a or 340 always alternates with a needle with a shorter butt 3412 or 34d.

Each of the cams 27, 29, 30 and 31 can be individually controlled to assume different positions, that is, different radial distances from the outer surface of the needle cylinder.

The cam 27 is controlled to take any one of three different positions: In a first position it is inactive with respect to needles with short butts 34b and 34d and, therefore, only acts on the needles with long butts 34a and 34c; in a second position it only acts on the needles with butts 34a, 34b and 340; and, in a third position, it acts on all needles.

The cam 29 is controlled to take any one of five different positions: In a first position, cam 29 is inactive for all needles; a second position cam 29 acts only on the needles with the longest butts 34a; in a third position cam 29 acts on all needles with long butts, that is, both on those with long butts 34c and on those with long butts 34a;

in a fourth position cam 29 acts on the needles with the butts 34a, 34b and 340; and finally in a fifth position it acts on all needles, including those with the shortest butts 34d.

Cam 30 is controlled to take any one of three different positions: In a first position cam 30 only acts on the needles with long butts 34a and 34c; in a second position it only acts on the needles with butts 34a, 34b and 340; and, in a third position, it acts' on all needles.

Cam 31.is controlled ;to take any one of three dilferent positions: In a first position, cam 31 is inactive for all 7 needles; in a second position cam 31 acts only on the needles with the longest butts 34a; and, in a third position, cam 31 acts on all needles with long butts, that is, needles with long butts 34c and long butts 34a.

FIG. 7 schematically illustrates a suitable device for effecting the foregoing control of the cams 27 and 29. The control device for cams 27 and 29 is actuated by steps 35 and 36 on cam rings 37 and 38 carried by the control drum 12. The ring 38 is contacted by the nose of a feeler lever 46 which is secured on a shaft 42 journaled in the machine frame. The shaft 42 carries an arm 44 which is in contact with a pin 46a on a slide 46 having the cam 29 extending therefrom in the direction radially toward cylinder 1. The cylindrical shell of cam assembly has a suitable opening (not shown) through which the cam 29 can extend more or less into the path of the needle butts. A spring 46b is connected to slide 46 to hold the pin 46a in contact with arm 44 and consequently to urge the nose of lever 40 against cam ring 38.

When the nose of feeler lever 40 is in contact with the ring 38, as shown on FIG. 7, the cam 29 is in the position closest to the circumference of the needle cylinder, and therefore is engageable with the butts of all needles. However, when drum 12 is turned to engage the cam steps 36 with the nose of lever 40, cam 29 is displaced radially outward from the circumference of the needle cylinder. Since the stepped cam 36 has four steps, this radially outward displacement can move cam 29 to four difierent radially outwardly displaced-positions. In the first of these displaced positions, cam 29 is made inactive only for the needles with the shortest butts 34d; in the second displaced position, cam 29 is made inactive for all needles with short butts 34b and 344, but remains active for the needles with long butts 34a and 34c; in the third displaced position, cam 29 is made inactive for the needles with the butts 34b, 34c and 34d; and, in the fourth position, caused by engagement of lever 40 with the highest of the cam steps 36, cam 29 is inactive with respect to all needles.

The cam ring 37 is contacted by the nose of a feeler lever 39 which is secured on a shaft 41 journaled in the machine frame. The shaft 41 carries an arm 43 which is in contact with a pin 45a on a slide 45 extending through a suitable opening (not shown) in the shell of the cam assembly 15. The radially inner end of slide 45 carries the left-hand kniting cam 27, and a spring (not shown) is connected to slide 45 to hold pin 45a in contact with arm 43 and, consequently, to urge the nose of lever 39 against cam ring 37.

When the nose of feeler lever 39 is in contact with the ring 37, as shown on FIG. 7, the cam27 is in the position closest to the circumference of the needle cylinder, thereby to be engageable with the butts of all needles. However, when ring 37 is turned to engage the cam steps 35 with the nose of lever 39, cam 27 is displaced radially outward from the circumference of the needle cylinder. Since the stepped cam 35 has two steps, this radially outward displacement can move cam 27 to two different displaced positions. In the first of these displaced positions, cam 27 is made inactive only for the needles with the shortest butts 34d; and, in the second displaced position, cam 27 is made inactive for all needles with short butts 34b and 34d, but remains active for the needles with long butts 34a and 340.

Referring now to FIGS. 3 and 4, it will be seen that the sinker cam ring 13 has an annular, downwardly opening cam groove 47 receiving the butts of the sinkers which are of different heights, as mentioned above, a group or zone of sinkers being provided with shorter butts 23a, and another group or zone of sinkers having taller butts 23b. The annular groove 47 has a cam portion 48 for displacing all of the sinkers radially outward to a certain extent. An additional or supplementary sinker cam 49 is insertable from above into the groove 47 in the region of the cam portion 48 so as to be operative to cause an outward movement of the sinkers that is greater than that caused by the cam portion 48. The division of the sinkers into a group-with short butts 23a and with long butts 23b is for the purpose of permitting the engagement and disengagement of the additional cam 49.

The additional cam 49 is secured on a stirrup 51 which is pivoted, at 52, on the machine frame (FIGS. 5 and 6). A spring 53 (FIG. 6) acts on stirrup 51 to urge the latter in the direction for introducing the supplementary cam 49 from above into a recess of the annular groove 47. The stirrup 51 bears on a profiled ring 54 which is angularly displaceable on the sinker cam ring 13. The ring 54 has, on its upper edge, a two-step cam 55. When the stirrup 51 bears on the ring 54 under the action of the spring 53, as shown on FIG. 6, the cam 49 is positioned to engage the butts of all sinkers. When ring 54 is turned so that the stirrup 51 is engaged by the first step of cam 55, the cam 49 becomes inactive for the sinkers with short butts 23a, and, when the ring 54 is turned to engage the second step of cam 55 with stirrup 51, the cam 49 is lifted to a position where it is inactive for all sinkers.

The displacement of ring 54 along a circular path on the sinker cam ring 13 is effected by the control drum 12 which is provided, for this purpose, with a three-step cam 59 (FIG. 6). The nose of a feeler lever 60 contacts the drum at the level of the cam 59. The lever 60 is secured on a shaft 61 carrying an arm 62 having a forked free end which engages a pin 63 secured on ring 54. A spring 64 acts on the arm 62 to urge the latter in the direction for maintaining the nose of feeler lever 60 in contact with the surface of drum 12. When the feeler lever 60 bears on the surface of the drum 12, the supplementary sinker cam 49 is fully extended into cam groove 47 for engagement with the butts of all sinkers. When the nose of feeler lever 60 is on the first step of cam 59, cam 49 is inactive for the sinkers with short butts 23a. When the second step of cam 59 engages the nose of lever 60, cam 49 is elevated to a position in which it is inactive for all sinkers. In FIG. 5, the completely inactive position of cam 49 is indicated by broken lines, while cam 49 is shown on FIGS. 3 and 4 in its active position for all sinkers.

The sinker cam assembly includes a further cam 50 which is normally in the inoperative position shown in full lines on FIGS. 3 and 4, and which can be inserted or moved to the position shown in broken lines in order to cause the radially outward or retracting movement of all of the sinkers to an extent greater than that achievable with the cams 48 and 49. In order to control the additional cam 50, the ring 54 is formed with a recess 56 which receives an arm 57 pivoted, at 58, on the machine frame and being secured with respect to the cam 50. A spring 65 acts on arm 57 so as to urge the latter into contact with the right-hand end, as viewed on FIG. 6, even though the arm 57 is shown approximately in the middle of the recess 56 merely for greater clarity. Ring 54 is angularly shifted to the extent necessary to effect movement of cam 50 from its inoperative position to its operative position, as shown in broken lines on FIGS. 3 and 4, only when the nose of lever 60 engages the top third step of cam 59 and thus also effects movement of cam 49 to its completely inoperative position.

The cams 30 and 31 for selectively raising and lowering the needles in advance of the yarn feed or guide 14 may be controlled by devices similar to those described above for the cams 27 and 29 with reference to FIG. 7.

The operation of the above knitting machine embodying this invention in producing a double, outwardly turnedover welt of a stocking will now be described with refer ence to FIGS. 10 to 13. In these views of the drawings, seven consecutive sinkers SI, SII .SVII, and six needles 3I, 3II 3V1 are shown schematically, with parts thereof broken away, in the positions occupied during successives phases of the welt production, and successive courses of the knitted fabric are indicated at A, B, C and D.

At the beginning of the knitting of a stocking, the first course A is knitted with the adjustable cams 27, 29 and 30 positioned so as to act upon the butts of all needles, while the cam 31 is positioned so that it can act only on the long-butt needles. Further, cam 49 is positioned so as to be engageable with the butts of all sinkers, while cam 50 is in its inoperative position. Since earns 27, 29, 30 and 49 are in their fully operative positions at the end of the production of the preceding stocking, there is-no need to adjust such cams for the commencement of the knitting of a stocking. However, upon the completion of the preceding stocking, the cam 31 is in its completely inoperative position, and such cam is adjusted from its completely inoperative position to the position where it can act only on the long-butt needles in the interval between the completion of the preceding stocking and the commencement of knitting of the next stocking. Such adjustment of cam 31 is, in the known manner, effected in two steps. More specifically, while cam 31 is being passed by the zone of the needle set made up of needles with butts 34c and 34d, cam 31 is moved to its position where it is engageable only with the needles with long butts 34a. Thereafter, during the engagement of cam 31 with the needle butts 34a, cam 31 is adjusted further inward to its position where it is also engageable with the needle butts 34c, that is, to the position where it can act on all of the needles with the long butts 34a and 340.

As a result of the above mentioned positioning of the cams for the production of the first course A, the sinkers are moved radially outward or retracted so as to present their lower knitting levels or ledges'16 for the forming of stitches. Although cam raises all of the needles, the following cam 31 lowers the alternate or long-butt needles (31, 3111, 3V etc.) so that such lowered needles cannot take the thread from the thread or yarn guide 14. Since only the short-butt needles remain raised after passage of the cam 31, only these needles (3H, 31V and 3V1) take the thread or yarn from the guide 14 for the knitting of the first course A.

In the case of a single feed machine, as illustrated, each course of the fabric is knitted during a complete revolution of the needle cylinder, but it is to be understood that the present invention can be embodied in knitting machines having multiple feeds, in which case, each course of the fabric is knitted during the turning of the needle cylinder through an angle equal to the angular spacing between the successive feeds.

During the forming of the second course B, that is, during the second revolution of cylinder 1 in the case of the illustrated single feed knitting machine, the several adjustable cams remain in the positions occupied during the forming of the first course A, with the exception that cam 31 is moved to its completely inoperative position, so that, during the forming of the second course B, all of the needles are operative and the stitches are again formed on the lower knitting levels 16 of the sinkers.

After these initial courses, that is, after the forming of the first course A and the forming of one or more courses knitted with the several adjustable cams in the positions described above for the second course B, the knitting of the major portion of the top or welt is begun. During the knitting of the major portion of the welt, it is necessary that the initial courses be retained for subsequent joining to the leg of the stocking upon the completion of the knitting of the welt. In order to achieve the foregoing, after the completion of the initial courses, for example, after the completion of the second course B, the stitches are no longer formed on the lower knitting levels 16, but rather are formed on the upper knitting levels 17 of the sinkers, while the initial courses A and B remain on the stems of the needles and are prevented from rising by the spurs or noses 18 of the sinkers.

In order to form the stitches on the upper ledges or knitting levels 17 of the sinkers, the retraction or radially outward movement of the sinkers, and the downward or knitting movements of the needles are reduced, and this is achieved by movement of earns 49 and 29 to their inoperative positions. However, since the yarn feed for the knitting of the major portion of the welt is the same as that for the formation of the initial or first two courses A and B, provision must be made for joining the courses A and B which are knitted on the lower levels 16 to the subsequent courses to be formed on the upper sinker levels 17.

According to the present invention, such joining of the courses knitted on the two levels can be effected in various ways, two of which are hereinafter described.

(a) In the first case, the third course C is formed with the cam 49 taken out or moved to its inoperative position and with the cams 27 and 29 positioned so as to act only on the long-butt needles (31, 3111 and 3V in FIG. 10), while earns 30 and 31 remain in the positions that they occupy for the second course B, that is, with cam 36 pcsitioned to act on all needles and cam 31 inoperative with respect to all needles mentary sinker cam 49 and of needle cams 27 and 29 to the positions mentioned above are effected in steps in the well known manner similar to that previously described with reference to the movement of cam 31. Since earns 27 and 29 only act on the long-butt needles, only those needles draw down the yarn of the third course C which is stretched across the upper knitting levels or-ledges 17 of the sinkers located between the adjacent long-butt needles. The long-butt needles are passed through the stitches of the lower course. During the following revolution of cylinder 1, that is, during the forming of the fourth course, cam 29 is moved, in a stepwise manner, to its fully inoperative position, while cam 27 is returned to its fully operative position where it acts on all of the needles, so as to prepare the knitting machine for the formation of the normal knit on the upper ledges 17 of the sinkers. For the forming of the fourth course, cam 31 is returned to its position where it acts only on the long-butt needles, while cam 30 is positioned so as to be inoperative with respect to all needles. Thus, the longbutt needles are lowered by cam 31 and cannot take the yarn for the fourth course, whereas the short-butt needles 3H, 31V, 3V1 etc., after havingbeen'raised by cam 32 to the level for taking the yarn, are permitted to remain at that level when passing the cam 31. Such short-butt needles draw down the yarn for the fourth course D and loop it through the yarn or thread of the third course C through the opeartion of the sinkers which push the thread of the third course C forward or radially inward with their upper spurs or noses 1?, before the needles return upwardly, so as to pass such thread behind the needle heads. The long stitches are thus turned over on the newly formed stitches thereby to join the stitches formed on the lower and upper knitting levels (FIG. 12). During the next revolution of the needle cylinder, cam 31 is again disposed in its inoperative position, and the formation of the knit proceeds normally on the upper sinker levels with all needles being operative.

(b) In the second case, joining of the courses knit on the lower sinker levels with the following courses knit on the upper sinker levels is effected by means of stitches which are relatively shorter than the joining stitches used in the first case described above. During the forming of the third course, the operation initially proceeds in the manner described for the first case, except that cam 30 is moved radially outward to the position where it acts only on the long-butt needles. Thus, only the long-butt needles shed their tongues or latches, while the latches of the shortbutt needles remain in engagement with the yarn of the third course C. During formation of the following or fourth course, cam 39 remains in the position where it acts only on the long-butt needles (FIG. 13) so that such needles shed their latches and the short butt needles do not shed their latches. In other respects, the operations performed during the formation of the fourth course are similar to those described for the first case and, when the short-butt needles 3H, 31V, 3V1 etc. come down with The movements of supplethe fed yarn for the fourth course D, such needles also take the thread of the third course and drag both threads downwardly, thus shortening the long stitches previously formed in the third course. However, during the forming of the fourth course, cam 31 is, in this case, retained in its wholly inoperative position so that the long-butt needles also take the thread and draw it downwardly. Since the long stitches have been shortened, the long-butt needles can loop through the stitches formed on the lower knitting levels.

For the forming of the following course, cam 30 is returned to its completely operative position where it acts on all the needles and knitting proceeds normally on the upper sinker levels. At this point, the remainder of the hosiery top or welt is knitted normally, while the first two courses A and B are retained by the needles and by the lower spurs or noses 18 of the sinkers which prevent such courses from rising to the upper sinker levels.

When the knitting of the welt or top has been completed, the initial courses A and B are joined to the last course of the top or welt prior to the knitting of the leg portion of the hosiery. Such joining of the courses A and B to the last course of the top or welt can be effected either by lowering the last course of the top or welt to the level of the lower ledges 16 of the sinkers and continuing with the knitting of the hosiery leg at this lower level, or by raising the courses A and B to the upper knitting levels 17 of the sinkers and then continuing with the knitting at such upper level for the rest of the hosiery.

(a) When joining of the courses A and B to the last course of the top or welt is effected by lowering of such last course, the sinkers can be of the type illustrated in FIG. 8 and, on completion of the top or welt, it is only necessary to effect the step-wise return of the supplementary cams 29 and 49 to their fully operative positions for the forming of the last course of the top in order to automatically obtain the desired joining of the courses A and B with such last course of the top.

(b) When joining of the courses A and B to the last course of the top or welt is to be effected by raising of the courses A and B to the upper levels 17 of the sinkers, the sinkers used may be of the type shown in FIG. 8, but are preferably of the type illustrated in FIG. 9.

When using sinkers of the typeshown on FIG. 8, the courses A and B are raised to the upper knitting level by causing the needles to effect an idle downward stroke, for example, by providing a cam (not shown) suitable for that purpose in the needle cam assembly, and, when the needles are raised again, by retracting the sinkers, for example, by means of cam t), so that the spurs or noses 18 of the sinkers no longer hold the courses A and B against upward movement and the needles can frictionally draw the courses A and B up to the upper knitting level.

When using the type of sinkers illustrated in FIG. 9, an idle downward stroke need not be imparted to the needles, and it is sutficient merely to retract the sinkers, as by means of the cam 50, so that the hump 25 disposed radially inward with respect to the lower level or ledge 16' of each sinker will raise the courses A and B to the upper knitting level. Having elevated the courses A and B to the upper knitting levels of the sinkers, the continuation of normal knitting on such upper levels will cause joining of the courses A and B with the course then being formed. Hence, closure of the double top or welt will be automatically obtained. Since the noses or spurs 18 or 18 which retain the first courses A and B in the lower grooves 20 or 20' of the sinkers are disposed at the outside of the tube of fabric formed during knitting of the remainder of the top or welt, the joint or connection of the courses A and B with the last course of the top or welt is disposed at the outside of the knitted tube. This is clearly shown on the schematic view of FIG. 14 where the first courses A and B of the double top or welt R are joined to the leg L of the stocking at the outside of the latter, and such double top or welt is outwardly turned-over. Since the courses A and B are joined to the leg of the stocking with every second stitch, such joint or connection is secure.

By eliminating the transfer hits, the dial carrying the same and the drive mechanism for such dial, thereby to substantially reduce the bulk of the mechanisms located above the needle cylinder, the arrangements embodying this invention are particularly useful on knitting machines which have a plurality of feeds.

Referring now to FIGS. 16 to 24, inclusive, another embodiment of the invention will be described, which embodiment is intended to improve the appearance and uniformity of the knitted fabric, particularly in the region where the initial courses of the top or welt formed on the lower knitting levels of the sinkers are connected to the following courses of the top or welt formed on the upper knitting levels, which region is clearly visible, as it lies at the outside of the stocking, when the welt or top is turned over outwardly and has its first courses joined to the last course of the top or welt. The embodiment of FIGS. 16 to 24 further improves the interlacing of the first row A of the top or welt with the following row B or rows formed on the lower knitting levels of the sinkers, and thereby avoids any possibility that such first row may be detached and thus adversely affect the apperance of the turned over welt.

The embodiment of the invention now being described is generally similar to that previously described herein and may, for example, be employed in a circular knitting machine of the type described with reference to FIG. 1.

Such knitting machine is provided with a set of needles 3 which alternately have long and short butts, as previously described with reference to FIG. 15, and is also provided with special sinkers 5 which may have a configuration substantially as shown on FIG. 8. The knitting machine used in connection with the presently described embodiment of the invention further has a cam mounted on top of the drum 12 (FIG. 1) which is engageable, from above, by a rod 101 which is guided for vertical sliding movement in frame 8 and engages, at its upper end, the underside of the toothed rim or gear 9 formed on the tube 7. Thus, when drum 12 is turned to engage cam 100 with rod 101, the latter is moved upwardly to effect corresponding upward shifting of tube 7, and hence of needle cylinder 1 and sinker support ring 2. Such vertical shifting of tube 7 is less than the axial width of gear 9 so that the vertical shifting of tube 7 is accomplished without disengaging gear 9 from driving gear 10.

As shown on FIG. 16, the needle cam assembly 15 of the embodiment now being described has, as its major parts, an upper central cam 26, a main knitting cam 27 which, in this case, is maintained in its completely or fully operative position throughout the knitting of the stocking, and a supplementary cam 29 disposed adjacent the lower end of the knitting cam 27 and being actuated by a device of the type previously described herein with reference to FIG. 7 so as to be selectively positioned to increase the downward movement of all of the needles of only the long-butt needles, or to be inactive with respect to all of the needles. The cam assembly 15' is further distinguished from the previously described cam assembly 15 of FIG. 2 in that the needle raising and lowering cams 30 and 31 of assembly 15 are replaced by a needle lifting or raising cam 30m for causing the the needles engaged thereby to rise to a position where their latches are cleared or shed and their books or heads are adapted to engage the thread fed by the guide 14. The cam 30m is also actuated, for example by a device similar to that described with reference to FIG. 7, so as to be selectively positoned for acting on all of the needles or on only the long-butt needles. Further, in the cam assembly 15, the guide ring 32m which .slidably supports the butts of the needles is shaped so that, after lowering of the needles by knitting cam 27, or by knitting cam 27 and supplementary cam 29, the needles are raised a dis tance which is insufiicient either for clearing or shedding 13 of the latches or for disposing the hooks or heads of the needles at a level where they are adapted to engage the thread or yarn fed by the guide 14. When the butts of the needles engage ring 32m, the hooks or heads of the needles lie substantially at the upper knitting levels 17 of the sinkers. On FIG. 16, the arrow 33 indicates the normal direction of movement of the needles with reference to the cams during the continuous rotation of the needle cylinder 1, and those cams which are operative during oscillation of the cylinder, for example, during the formation of the toe and heel of the stocking, are not illustrated on FIG. 16.

Referring now to FIG. 7, it will be seen that the cam assembly 13 for actuating the sinkers is generally similar to the previously described cam assembly 13 and particularly includes a supplementary cam 49 which is movable form above into the groove 47 in the region of the cam 48 so as to increase the retraction or radially outward movement of the sinkers upon engagement of the butts 23 of the sinkers by cam 49. The cam 49 of assembly 13' is also actuated by a device of the type previously described with reference to FIG. 6 so as to be selectively positioned in an operative position, where it is engageable with the sinker butts, or in an inactive position where cam 49 is withdrawn from groove 47.

Of course, in order to permit the engagement and disengagement of cam 29 and 30m with the needle butts and of cam 49 with the sinker butts, the movements of such adjustable cams are effected in a stepwise manner, and the long and short butts of the needles and the butts of the sinkers are of reduced dimensions over limited angular zones of the needle cylinder to cooperate with such step-wise displacement, as previously described herein with reference to FIG. 15.

Referring now to FIGS. 18 to 21, it will be noted that the odd-numbered needles 31, 3III, 3V and 3VII once again represent long-butt needles, while the even-numbered needles 31L 31V and 3V1 represent short-butt needles. Further, in these views, the successive courses are identified by the letters, A, B, C.

For the formation of the first course A at the beginning of the knitting of a-stocking, that is, the first course of the top or welt, the supplementary cam 29 is disposed in its fully operative position, that is, where it can act on all of the needles, and the cam 39m is positioned so that it can act only onthe long-butt needles SI, 3111, etc. The supplementary cam 49 controlling the sinkers is also disposed in its operative position for the formation of the first'course A. Consequently, the first course A is formed on the lower knitting levels 16 of the sinkers 5, and only the long-butt needles are raised by the cam 39m to engage the thread fed by the guide 14.

For the formation of the second course B, and also possibly a third course B the cam 3i'3m is positioned to act on all the needles so that smooth normal knitting occurs during the courses B and B on the lower knitting levels 16 of the sinkers.

After the initial courses, whichmay be two or three in number, the next course C is formed with the supplementary sinker cam 49 in its inoperative position and with the supplementary needle cam 29 positioned to act only on the long-butt needles, while the cam 30m remains in the position for acting on all of the needles. By reason of the foregoing positioning of the cams, the course C is formed on the upper knitting levels or ledges 17 of the sinkers. However, since the downward strokes of the long-butt needles are increased by the cam 29, such needles knock their loops over the corresponding loops in the preceding course, for example, in the third course B which were formed on the lower knitting levels of the sinkers. At the conclusion of the formation of the fourth course C, the threads are interlaced as shown diagrammatically on FIG. 18. It will be noted that the short butt needles 3H, 31V, etc., having engaged the thread fed by the guide, form loops on the upper knitting levels 17 of the sinkers, but do not knock their loops over the lower loops or meshes, as the short-butt needles are not engaged by the supplementary cam 29 and thus are only lowered by lowered position by the grooves 20 of the sinkers so as to be available for joining or connecting the beginning of the turned over top or welt with the leg of the stocking when the top or welt has been completed. Throughout the knitting of the top or welt, the loops of the course B carried by the shanks of the short-butt needles remain in lowered positions on such shanks so as to avoid any interference with the formation of meshes or loops on the same needles in registry with the upper knitting levels of the sinkers, as is indicated by the interlacing of the meshes shown on FIG. 22.

The course C described above may be followed, if desired, by a course C formed with the same arrangement of the cams as has been described above for the course C so as to provide an additional course of smooth loops 7 or meshes, as indicated on FIG. 23. Such auxiliary course C having smooth meshes or loops is not illustrated on FIGS. 18 to 21 for the purpose of simplifying the draw- 'ings.

For the formation of the following course D, the cam 3am. is positioned so as to act only on the long-butt needles 3i, 3111, etc. Consequently, the short-butt needles 3II, 31V, etc. do not clear their latches and are not raised to the level required for taking the thread or yarn from the guide 14. Only the long-butt needles engage the thread.

' However, the cam 27 lowers all the needles and, while the long-butt needles draw the new thread downwardly, the short-butt needles which have refused the new thread, again lower the loops which were formed during the preceding course, as shown on FIG. 19. By reason of such lowering of the loops of the preceding course on the shortbutt needles, and through an effect similar to that of a pulley system, the loops released by-the long-butt needles in the preceding course are raised slightly. In order to allow the long-butt needles to release and knock over the newloops onto the loops of the preceding course, it is necessary to effect further lowering of the long-butt needles, and this is achieved by leaving the cam 29 in the position to act only on the long-butt needles during the forming of the course D. Therefore, the loops of the course D formed with the long-butt needles are elongated by an amount" corresponding to the further downward stroke of such needles caused by the cam 29. Taking into account the fact that the preceding loops on the long-butt needles tend to rise by reason of the above described pulley efiect, and with a view to obtaining the knocking of the new loops over the preceding loops, it is not necessary to provide such a long elongation of the loops, that is, an elongation of the extent provided by the cam 29, and consequently it may be preferable to resort to other means for effecting the slight elongation of the loops, for example, resort may be advantageously had to the conventional mesh enlarging means provided in all standard circular knitting machines.

In fact, if during the formation of the course D, the needle cylinder 1 together with the support ring 2 carrying the sinkers 5 are raised by the cam 16%) and rod 101' 4 (FIG. 1) so as to be displaced upwardly relative to the needle cam assembly 15, the needles 3 cannot follow such upward shifting of the needle cylinder as their butts are engaged by the cams of assembly 15'. Thus, the sinkers 5 rise relative to the needles and carry upwardly the loops of the preceding course C which were released by the long-butt needles. Such upward'movement of the loops of course C which were released by the long-butt needles is again achieved with the above mentioned pulley ef-. fect since the loops which have not been released in course C are engaged by the short-butt needles. Thus, it 7 is possible to obtain knocking over of the new loops formed by the long-butt needles over the preceding formed loops, and this shows an advantage over the previously described arrangement wherein exaggerated elongation of the loops in course D is effected by the cam 29. In fact, the upward shifting of cylinder 1 and of the sinker carrying ring 2 by the mesh-enlarging means can be accurately limited and predetermined by suitably selecting the height of the cam 100.

The interlacing of the threads obtained during the formation of the course D is substantially as illustrated on FIG. 20.

For the formation of the following course E, the supplementary cam 29 is moved to its wholly inactive or inoperative position, if this has not been done for the preceding course D, and the cam 30112 is moved to the position where it acts on all needles. Consequently, all of the neeedles are raised by cam 30m to clear their latches end to engage the new thread which is acted upon in I i the usual manner to form a smooth mesh 'or loops. Such loops are formed on the upper knitting levels 17 of the sinkers and the loops of course D drop over the elongatedloops in course C so as to bind them together. FIG. 21 diagrammatically shows the interlacing of the threads or yarns following the formation of the course E. It will be apparent from FIG. 21 that the loops in course E form meshes or stitches with the loops in course D in registry with the long-butt needles and also with the loops in course C registering with the short-butt needles. Such meshes or stitches are illustrated in staggered positions on FIG. 21 so as to clarify the drawing.

The course E is followed by as many courses of smooth or normal stitches as are required for the formation of the welt or top of the stocking. When the knitting of the welt or top is completed, binding of the loops held in lowered positions on the shanks of the short-butt needles with the loops of the last course of the top or welt is effected by restoring the supplementary earns 29 and 49 to their fully operative positions and thereafter forming the remaining sections of the stocking or hosiery on the lower knitting levels 16 of the sinkers.

As shown on FIGS. 22, 23 and 24, where the numerals I, II, III, etc., indicate the rows or wales of meshes or stitches formed by the needles 31, 311, 3111 etc., the meshes or stitches formed in accordance with the last described embodiment of the invention have a perfectly uniform interlacing and structure and are uniformly stretched. Further, the first courses A and B are propely intelaced and cannot run or ladder, thereby surely avoiding any excessive strains or defects in appearance.

Although illustrative embodiments of this invention have been described in detail herein with reference to the accompanying drawings, it is to be understood that the present invention is not limited to those specific embodiments, and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the invention, except as defined in the appended claims.

What is claimed is:

1. In a circular knitting machine for the manufacture of stockings and socks with double outwardly turned-over tops, the combination of a needle cylinder carrying alternately arranged needles with long and short butts, respectively, sinkers movable radially between said needles and each having upper and lower knitting ledges with the upper knitting ledge being disposed radially outward with respect to the lower knitting ledge and a groove below the upper knitting ledge, a main knittingcam for actuating the needles and a main sinker cam for retracting the sinkers during normal knitting operation, a supplementary needle cam associated with the main knitting cam and operative to increase the down-stroke of the needles, a supplementary sinker cam associated with said main sinker cam for further retracting the sinkers, and actuating mcchaHiSm QI said supplementary needle and sinker cams rendering said supplementary cams both operative during knitting of at least the first two courses of the double top, thereby to form the stitches of these first courses at the level of said lower knitting ledges, and, during the knitting of at least the immediately following course rendering said supplementary sinker cam inoperative while said supplementary needle cam remains operative to increase the down-stroke of at least the long-butt needles and during the knitting of the next course is rendered completely inoperative with respect to all of the needles so that thereafter during the knitting of the double top the knit is formed on the upper ledges of the sinkers and is joined to said first courses which are held down on the stems of the needles.

2. In a circular knitting machine, the combination as in claim 1; wherein said main knitting cam and said supplementary needle cam for effecting the downward stroke of the needles are rendered operative only with respect to the long-butt needles during the knitting of said course immediately following said first courses.

3. In a circular knitting machine, the combination as in claim 2; further comprising a cam for actuating the needles to effect clearing of their latches, and means rendering said cam for effecting clearing of said latches of the needles operative only with respect to the longbutt needles during the knitting of the two courses following said first courses of the top.

4. In a circular knitting machine, the combination as in claim 3; wherein each sinker has a hump in front of its lower knitting ledge; and further comprising cam means acting on said sinkers upon completion of the knitting of the double top to further retract said sinkers sufficiently to cause said humps to raise the knit formed on said lower ledges up to the level of said upper ledges for joining with stitches formed on the latter.

5. In a circular knitting machine, the combination as in claim 1; further comprising thread guide means located in advance of said main knitting cam for feeding thread to the needles, and additional cam means adapted to act on the butts of said needles in advance of said thread guide means to determine which of the needles clear the latches thereof and the positioning of the needles for taking thread from said thread guide means.

6. In a circular knitting machine, the combination as in claim 5; wherein said additional cam means includes a contoured guide n'ng engageable with the needle butts from below to raise all needles to a level for taking thread from said thread guide means after the needles move past said supplementary needle cam, and additional needle raising and lowering cams located successively in advance of said thread guide means and being movable for respectively raising selected needles so as to clear the latches thereof and lowering selected needles below said level for taking thread from said thread guide means.

7. In a circular knitting machine, the combination as in claim 6; wherein said main knitting cam and said supplementary needle cam are rendered operative only with respect to the long-butt needles during the knitting of said course immediately following said first courses; said additional needle raising cam is operative with respect to all of the needles at all times; and said additional needle lowering cam is operative only with respect to said longbutt needles during the knitting of the initial one of said first courses and during the knitting of said next course after said course immediately following said first courses, and is otherwise inoperative with respect to all of said needles.

8. In a circular knitting machine, the combination as in claim 6; wherein said main knitting cam and said supplementary knitting cam are rendered operative only with respect to the long-butt needles during the knitting of said course immediately following said first courses; said additional needle raising cam is rendered operative with respect to only said long-butt needles during the knitting of said course immediately following said first courses and of the next course, and is otherwise operative with respect to all of the needles; and said additional needle lowering cam is operative only with respect to said long-butt needles during the knitting of the initial one of said first courses and is otherwise inoperative with respect to all of the needles.

9. In a circular knitting machine, the combination as in claim wherein said additional cam means includes a contoured guide ring engageable with the needle butts from below to support the needles at a level below that at which they can take thread from said thread guide means, and a movable needle raising cam located in advance of said thread guide means for raising selected needles sufficiently to clear the latches thereof and to take thread from said thread guide means; and

wherein said supplementary needle cam is operative to increase the down-stroke of only the long-butt needles during the knitting of at least two courses following said first courses while said supplementary sinker cam is inoperative with respect to all needles, and said needle raising cam is rendered operative to act only on said long-butt needles during the initial one of said first courses and the last one of said at least two courses following the first course, said needle raising cam being otherwise rendered operative to act on all of said needles.

10. In a circular knitting machine, the combination as in claim 5; wherein said additional cam means includes a contoured guide ring engageable with the needle butts from below to support the needles at a level below that at which they can take thread from said thread guide means, and a movable needle raising cam located in advance of said thread guide means for raising selected needles sufficiently to clear the latches thereof and to take I thread from said thread guide means; and

1 8 wherein said supplementary needle cam remains operative to increase the down-stroke of only said longbut needles only during the knitting of said course immediately following said first courses, and said needle 5 raising cam is rendered operative to raise only the long-butt needles during the knitting of the initial one of said first courses and the knitting of said next course after said course immediately following the first courses, said needle raising cam being otherwise operative to raise all of the needles.

10 11. In a circular knitting machine, the combination as in claim 10; further comprising cam means operative, during the knitting of said next course after the course immediately following the first courses, to raise said needle cylinder and sinkers with respect to said main knitting cam, thereby to efiect relative upward movement of the sinkers with respect to the needles under the control of said main knitting cam.

References Cited by the Examiner UNITED STATES PATENTS 1,079,267 11/1913 Scott 66-173 1,148,055 7/1915 Scott 66-41 FOREIGN PATENTS 1,289,308 2/1962 France.

940,708 10/ 1963 Great Britain.

OTHER REFERENCES Loimann, Ger. App. No. 1,079,781, pub. April 14, 1960.

DONALD W. PARKER, Primary Examiner.

W. C. REYNOLDS, Assistant Examiner. 

1. IN A CIRCULAR KNITTING MACHINE FOR THE MANUFACTURE OF STOCKINGS AND SOCKS WITH DOUBLE OUTWARDLY TURNED-OVER TOPS, THE COMBINATION OF A NEEDLE CYLINDER CARRYING ALTERNATELY ARRANGED NEEDLES WITH LONG AND SHORT BUTTS, RESPECTIVELY, SINKERS MOVABLE RADIALLY BETWEEN SAID NEEDLES AND EACH HAVING UPPER AND LOWER KNITTING LEDGES WITH THE UPPER KNITTING LEDGE BEING DISPOSED RADIALLY OUTWARD WITH RESPECT TO THE LOWER KNITTING LEDGE AND A GROOVE BELOW THE UPPER KNITTING LEDGE, A MAIN KNITTING CAM FOR ACTUATING THE NEEDLES AND A MAIN SINKER CAM FOR RETRACTING THE SINKERS DURING NORMAL KNITTING OPERATION, A SUPPLEMENTARY NEEDLE CAM ASSOCIATED WITH THE MAIN KNITTING CAM AND OPERATIVE TO INCREASE THE DOWN-STROKE OF THE NEEDLES, A SUPPLEMENTARY SINKER CAM ASSOCIATED WITH SAID MAIN SINKER CAM FOR FURTHER RETRACTING THE SINKERS, AND ACTUATING MECHANISM FOR SAID SUPPLEMENTARY NEEDLE AND SINKER CAMS RENDERING SAID SUPPLEMENTARY CAM BOTH OPERATIVE DURING KNITTING OF AT LEAST THE FIRST TWO COURSES OF THE DOUBLE TOP, THEREBY TO FORM THE STITCHES OF THESE FIRST COURCES AT THE LEVEL OF SAID LOWER KNITTING LEDGES, AND, DURING THE KNITTING OF AT LEAST THE IMMEDIATELY FOLLOWING COURSE RENDERING SAID SUPPLEMENTARY SINKER CAM INOPERATIVE WHILE SAID SUPPLEMENTARY NEEDLE CAM REMAINS OPERATIVE TO INCREASE THE DOWN-STROKE OF A LEAST THE LONG-BUTT NEEDLES AND DURING THE KNITTING OF THE NEXT COURSE IS RENDERED COMPLETELY INOPERATIVE WITH RESPECT TO ALL OF THE NEEDLES SO THAT THEREAFTER DURING THE KNITTING OF THE DOUBLE TOP THE KNIT IS FORMED ON THE UPPER LEDGES OF THE SINKERS AND IS JOINED TO SAID FIRST COURSES WHICH ARE HELD DOWN ON THE STEMS OF THE NEEDLES. 